Magnitude and frequency relations of bankfull flows and bed-material entrainment in the Llano River watershed, Central Texas, USA

The physical geography of medium-sized rivers, focusing on the Southeastern and South-Central United States. Part II

Auteur(s) et Affiliation(s)

HEITMULLER, F.T.

Dep. of Geography and Geology, Univ. of Southern Mississippi, Hattiesburg, Etats-Unis

MOSSA, J.

Dep. of Geography, Univ. of Florida, Gainesville, Etats-Unis

HEITMULLER, F.T.

Dep. of Geography and Geology, Univ. of Southern Mississippi, Hattiesburg, Etats-Unis

Description :
Bankfull channel geometry and bed-material entrainment are examined in the Llano River watershed in central Texas, which is characterized by mixed alluvial-bedrock boundaries and a highly variable flow regime. Field data, including cross-section surveys and sediment samples from 17 sites, are coupled with one-dimensional hydraulic models and flood-frequency analyses to compute recurrence intervals of bankfull and entrainment conditions. Recurrence intervals of flows that entrain median-sized bed material are consistently less than 1 year, whereas flows that define bankfull morphology range from 1 to 4 years (median of 1.75 years). Recurrence intervals of flows responsible for incipient entrainment of relatively coarse bed material are typically less than 1.5 years, but complete mobilization of this size fraction occurs less frequently than bankfull flows.

Type de document :
Article de monographie

Source :
Physical geography, issn : 0272-3646, 2011, vol. 32, n°. 6, p. 533-560-, Références bibliographiques : 4 p.

Date :
2011

Editeur :
Pays édition : Royaume-Uni, Abingdon, Taylor and Francis

Langue :
Anglais